Brits up and down the country worry about invasive plants - like Japanese Knotweed - causing chaos to their homes and gardens.

Rightfully so since experts have described the likes of Japanese Knotweed as a "horticultural horror story".

The aggressive plant not only boasts a menacing growth rate but also has roots which burrow deep into the underground – sometimes up to 3 metres down.

It also spreads horizontally in any direction and can spread far. Its relentless strength can even shatter concrete, foundations, and patios – no barrier is safe from its invasion.

If you discover Japanese Knotweed on your property, you mustn’t delay, according to the experts at PriceYourJob.co.uk.

"The longer it lingers, the greater the potential damage," the pros warned.

They added: "This invasive weed can infiltrate your home's foundations, walls, and floors, leading to expensive repairs".

To help you tackle it, gardening and plant expert Harry Bodell at PriceYourJob.co.uk has created this guide. 

What do I do if find Japanese Knotweed?

Since Japanese Knotweed can spread very easily and can be very destructive, the plant can be difficult to tackle.

The experts urge that complete eradication is essential to prevent regrowth, and therefore, removing the extensive root system often requires a mechanical digger.

Japanese Knotweed UK Law

Japanese knotweed is legally classed as a controlled plant under the Wildlife and Countryside Act 1981 section 114 (2) (WCA 1981) under UK law.

It's important to note that it is not illegal for you to have Japanese knotweed on your property.

However, it is against UK law to cause or allow the plant to spread in the wild.

It is legal to have Japanese Knotweed on your property but you can be prosecuted or given a community protection notice for causing a nuisance if you allow it to spread onto anyone else’s property.

Harry added that since the disposing of the plant and any contaminated soil is strictly regulated, it must be taken to a designated landfill site.

The expert recommends consulting an expert to ensure it is properly removed, and disposed of, and the risk of the weed returning is minimized.

How to get rid of Japanese Knotweed

If you decide to tackle Japanese Knotweed yourself, the expert suggests herbicide treatment as an option.

Here's a breakdown of the steps involved:

Plan Meticulously: Before diving in, assess the surrounding area. Are there nearby schools, playgrounds, or water sources that could be affected by herbicide overspray? Inform your neighbours about the treatment schedule to minimize exposure risks. Choose a late spring or early autumn window when the plant is actively growing.

Safety First: Don't underestimate the importance of proper safety gear. Wear overalls, a safety mask, gloves, and a face shield for protection. Sheets, tarpaulins, and rubble sacks will also come in handy.

Weather Matters: Choose a dry day with no rain forecast, as most herbicides can harm desired plants as well. Avoid windy conditions if using a spray application.


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Targeted Application: A garden sprayer is effective for applying herbicide, but use caution near water sources or sensitive areas. Alternatively, a roller, cloth, sponge, or brush can be used for localized application. Remember to wear gloves and shield nearby plants with tarpaulins. The herbicide should thoroughly cover the leaves and stems. For enhanced effectiveness, inject some herbicide directly into the stems near the base. Specialized tools are available for professionals, but a simple cut at the base followed by pouring herbicide into the opening can suffice.

Careful Disposal: Once cut, place all Knotweed material in sturdy plastic rubble sacks. Remember, this is hazardous waste and requires disposal at a designated landfill site. Check with your local council to see if they offer any collection services for Japanese Knotweed.

Persistence is Key: Eradicating Japanese Knotweed is a long-term battle, not a quick fix. A single treatment won't do the trick. Be prepared to repeat the process 2-3 times a year for several years (3-5) until the weed is completely eradicated and shows no signs of regrowth.